Smoke screen equipment



April 1946- w. SINTON ET AL 2,399,265

ZSMOKE SCREEN EQUIPMENT 2 Sheets-Sheet 1 Filed Jan. 18, 1938 Ewenvvns: Z0 z JiYdDvo E 12 Sherwwo George d,6'7za'cZwic7t April 1946. w. SINTON ETAL SMOKE SCREEN EQUIPMENT Filed Jan 1a, 1938 2 Sheets-Sheet 2 wewafvrs: illiam Simian, 5E R Jkermwuz @eov'ge d Cfiaaz aia Patented Apr. 30, 1946 UNITED STATES PATENT OFFICV SMOKE SCREEN EQUIPMENT William Sinton and Forrest I. Sherman, United States Navy, and George A. Chadwick,.Washington, D.

(Granted under the act of March 3,, 1883, as amended April 30, 1928; 370 0. G. 757) This invention relates to means and methods for forming smoke screens and has among its objects:

To eliminate the formation of thin zones in .smoke screens;

our invention with a portion of the enclosure removed;

Fig. 2 is a section substanitally on the line 2-2, Fig. 1; Fig. 3 is a detailed view taken on the line 3-3, Fig. 1;

Fig. 4 is a detail of a form of our invention embodying certain changes from Fig. 1;

Fig. 5 is a section substantailly along the line 55, Fig. 4.

It is well-known to those conversant with this art that smoke screens formed by prior apparatus have not been uniformly of maximum effectiveness due to the presence of thin zones caused by variations in the rate of expulsion of the smoke forming material. overcomes this defect and insures optimum concealment.

As depicted in Fig. 1, the tank .6 that contains the smoke forming material has in general the external contour of a bomb and is provided with attaching elements 1 for securing the tank 6 to the usual bomb racks of military aircraft, though it may be attached thereto in any other suitable manner. The smoke forming material passes from the tank 6 through a pipe 8 that has an open end adjacent the lowermost portion of the tank 6 and is connected, in the order named, to a gate valve 9, an operating valve III, a fitting l I, and a discharge pipe I2 that is pivotally connected to the fitting II and is preferably streamlined in fore and aft cross section. The gate valve 9 is normally closed but is opened just prior to taking 01f when the equipment is to be used. The valve 10 is operated by means of a shaft The present invention 5 at its other end an opening IE to be engaged by a cord or cable that extends to the cockpit of the craft to permit remote operation of the valve 9. The lever 'l 4 is slotted longitudinally and through this slot extends a spring retainer rod 16 that is pivoted at l T to the valve l0 and carries a Spring l8 under compression between a head I9 at the outer end of the rod and a rocking spring abutment 2!! that is slidable on the rod [6.

The smoke forming material is expelled from .tank 5' by a suitable expansible medium under pressure in the flask 2|, such medium being preferably carbon dioxide due to the fact that this gas is chemically inert. The fiuid medium is transmitted through a, pipe 22 that has preferably connected in it pressure regulating valves disposed adjacent the operator, but since such means are common'and' well-known and consti tute no part of the present inventionthey are not shown. The pipe 22 is connected through valve 23 to pipe that extends into tank 6 and discharge adjacent to the upper surface thereof. The valve 23 is likewise normally closed but is opened immediately rior to the beginning of the flight. Stirrup 25' is provided to form a connection with some fixed part of the craft, through a rigid linkage, to fix the angular position of the discharge tube l2. A substantially conical housing for the valves is formed of two mating sections 26 that are secured to the tail end of the tank 6 and thereby complete the streamlining of the assembly and reduce parasitic drag during flight. Bracket 21 is fixed to the section 26 and is connected to the fitting I l, as shown in Fig. 3, to constitute a steadying support for the valves 9 and i0 and the discharge tube [2.

The useof the'constant fluid pressure to expel the smoke forming material results in a uniform flow thereof from the tank 6 and therefore produces a smoke screen that is of substantially unvarying thickness and density, whereas in prior apparatus, such as those employing suction to remove the smoke forming material from the tank, discharge varying quantities of the smoke forming material and hence do not produce a smoke screen of uniform effectiveness.

It appears that the mode of operation is obvious since, with valves l0 and 23 opened before beginning the flight, movement of lever it to the dotted line position shown in Fig. 2 leaves an unobstructed conduit for the smoke forming material from the tank 6 out through discharge tube l2 and this operation of lever I4 is effected by pulling a cord or cable attached to the lever,

13 to which i fixed one end of lever l4 having as above set forth. The pressure control device noted that a flanged coupling 28 is used for con-,

meeting the valve 23 to the pipe 24 instead of a plane screw-threaded connection as in Fig. l.

Likewise, a tubular and closing member 29 for the pipe 24 i provided and bears against the coupling 28 whereby a more rigid construction and a more certain support for; valve 23 are effected.

According to the provisions of the patent statutes we have set forth the principle and mode of operation of our invention and have'illustrated and described what we now consider to represent its best embodiment. However, we desire tohave it understood that within the scope of the appended claims the invention may be practiced otherwise than sis-specifically illustrated anddescribed.

Piping, regulator valve, cut-off valves'9 and 23 and operating valve- In arev so proportioned that freezing due toover-rapid expansion of the gas is prevented and no parts are subjected to excessive pressure. The cut-oil? valve 9 keeps the operating valve l0 free from contact with the chemicals until take-off and permits removal and disassembly of the operating valve for cleaning and adjustment. 5

l The invention herein described and claimed may be used'and/or manufactured by or, for the Governmentof the United States of America for governmental purposes without the payment of any royaltie thereon or therefor.

We claim: 1

1. In combination, a tankadapted to contain smoke-fuming materials and provided with means for attachment to the bomb rackof an aircraft a hollow conical tail-piece cooperating with said tank to give an external bomb-like contour, mean to introduce into said tank, under regulated-pressure, a gas chemically inert with respect to the said materials, theparts of said means being proportioned to prevent freezing due to expansion of said gas, and means forming an outlet conduit for discharging said materials including a quick-opening gate valve, a second valve, a pivotally'mounted lever to actuate said second valve, resilient means acting to maintain said second valve normally closed and an outlet tube having one end pivotallyassociated with said valves, said tube being streamlined'in cross section, said valves, said resilient means and the pivotally mounted end of said tube being enclosed in said tail-piece.

2. In combination, a tank adapted to contain smoke-forming materials, a hollow conical tailpiece cooperating with said tank to give an external. bombelike contour, means to introduce into said tanlcunder regulated pressure, a gas chemically inert with respect to the said materials, the parts of said means being proportioned to prevent freezing due to expansion of said gas, and means forming an outlet conduit for discharging said materials including a quick-opening gate valve, a second valve, a pivotally mounted lever-toactuate said second valve, resilient means acting to maintain said second valve normally closed and an outlet tube having one end pivotally associated with said valves, said tube being streamlined in cross section, said valves,

said resilient means and the pivotally mounted end of said tube being enclosed in said tail-piece.

-3. In combination, a tank adapted to contain smoke fcr'ming materials, a hollow conical tailpiece cooperating with said tank to give an external bomb-like contour, means to introduce into said tank, under regulated pressure, a gas chemically inert with respect to the said materials, the parts of said means being proportioned to prevent freezing due to expansion of said gas, and meansforming an outlet conduit for discharging said materials including a quick-opening gate valve, asecond valve,-a pivotally mounted lever to actuate said second valve,means actingto maintain said second valve normally closed and'an outlet tube having one end pivotally associated with said valves, said tube being streamlined; in cros section, said valves, said resilient means and the pivotally mounted end of said tub being enclosed in said tail-piece.

4. In combination, a tank adapted to contain smoke-forming materials, a hollow conical tailpiece cooperating with said tank to give an external bomb-like contour, means to introduce into said tank, under regulated pressure, a gas chemically inert with respect to the said materials, the parts of said means being proportioned to prevent freezing du to expansion of said gas,

and means forming an outlet conduit for discharging said materials including a quick-opening gate valve, a second valve, a pivotally mounted lever to actuate said second valve; means acting to maintain said second valve normally closed and an outlet tube having one end pivotally associated with said valves, said valves, said resilient means and the pivotally mounted end of said tube being enclosed in said tail-piece.

WM. SINTON.

FORREST P. SHERMAN.

, GEORGE A, CHADWICK. 

